Logging operations often make use of wheeled or track type vehicles with a boom mounted grapple for grasping stacks of logs and moving the logs to a loading area. The typical grapple is freely pivoted at the end of the boom, and will swing to a substantially vertical position regardless of the angular orientation of the vehicle. This is not a problem in situations where the ends of the logs in the stack are even, and the logs are situated in an easily accessible orientation. However conditions are not always ideal, and situations can arise where the vehicle operator will have a great degree of difficulty in maneuvering the grapple into a position for grasping the stack.
Many operators will have difficulty positioning a grapple on a stack of logs that is on a steep incline. The grapple, being loosely suspended on the boom, will swing to a vertical orientation as the vehicle moves up the incline. Thus the grapple will swing in close to the vehicle. The boom can be lowered to extend the boom reach, but the grapple, being vertical will not reach as far as the boom. Thus the effective reach of the boom is compromised on inclined terrain.
It is an objective of the present invention to provide control of grapple movement toward and away from the grapple so the vehicle operator has a greater degree of control of the grapple position, regardless of the degree of inclination of the vehicle.
It is a further objective to provide a grapple positioning device that may be mounted as a retrofit to existing grapple and boom combinations.
It is a still further objective to provide a grapple positioning device that is easily mounted to a boom and grapple.
It is another objective to provide a grapple positioning device that is simple in construction and inexpensive to maintain and operate.